Running form: hard surfaces are not the problem
By Trevize1138
By Trevize1138
I keep hearing this fallacy repeated not just here but everywhere running on concrete or asphalt is brought up. There's an automatic assumption that hard surfaces are the source of damaging impact from running. The trouble with that is it's just an assumption and I have yet to come across research backing up this assumption.
The assumption does have its reasons, of course, as there's lot of anecdotal stories about people's joints hurting or overall feeling discomfort after running on paved surfaces. In addition to this people say they don't feel the same discomfort or pain on dirt trails or gravel. Continuing the assumption, it's theorized that dirt and gravel are "softer" than pavement.
I fell for this exact fallacy. I much preferred running on the gravel roads near my house than the paved ones. Transitioning from gravel to paved was just awkward. My form felt all off and my footfalls felt harsh. Thing is, the gravel I run on isn't a soft surface at all. I live in farm country and I'm sharing these gravel roads with large 18-wheelers loaded with harvested corn kicking up dust at 45mph (LPT: always run on the upwind side of the road to avoid choking on dust).
Not a soft surface.
What was the difference, then? I was running in Trail Glove 2s which have no cushioning at all but the gravel roads were far more comfortable than click-clacking along pavement. The difference was how uneven the gravel roads are compared to paved. TG2s had rock plates but they didn't protect against larger rocks so I was watching where I was stepping all the time to avoid pain. Miles and miles of mindful running being careful where I put my feet. Once I got to the pavement I didn't need to watch any more. My stride opened up, I relaxed in all the wrong ways and "click-clack-click-clack".
Instinctual movements are powerful things. If you don't think your gait changes with the surface try writing with your non-dominant hand. It took me a couple years to figure out that was happening and then started working on how to run on even, level surfaces the same way I was running on rough, uneven ones. The biggest help for that, of course, was going unshod.
Take the shoes off and everything is like those nice, comfortable trail or gravel runs. You're watching where you step with every step, completely mindful and the result are gentle steps. You run with finesse and care rather than mindlessly stomping along.
The research backs this up: https://www.nature.com/articles/nature08723. Put something soft under your feet and your instinctual movements can get a bit messed up. In Born to Run there's even mention of a study on gymnasts landing on thin, hard mats vs thick, soft ones. The secondary impact was greater on the thick, soft mats. The theory there is feet were instinctively pushing through that cushioning to get to solid ground.
The analogy I like to think of is standing on a water bed where your whole body is struggling to stay steady. Jump off the bed onto the floor and you can relax. Solid, firm ground. Cushioning under your feet in shoes is only less bad than a water bed but it's a similar effect.
My father-in-law is a prime example of what happens to feet, ankles and padded shoes over time. He's overweight and prefers wearing athletic shoes with padding. Over time the cushioning on those shoes gets compressed to the inside as his feet constantly pronate over, pushing through to find solid ground. Once it gets too bad he gets new shoes and the battle starts all over again.
Keep this in mind next time you're struggling with paved surfaces. Correlation is not causation and hard ground is hard ground. Even a dirt nature trail hardens up nicely as the season progresses and enough feet and bikes have beaten on it. Run on every surface with careful, gentle steps and you'll run injury-free and efficient.
Another key factor:
Traction.
People usually view traction with a singular, linear metric: more traction is better than less traction. But that goes entirely counter to people finding gravel and dirt more comfortable than paved. Aside from wearing track spikes traction doesn't get much better than rubber on pavement. If you've got aggressive, off-road tread on your shoes that can give excellent traction on a trail but even then the traction you get is not at all consistent. You then view traction as a nice-to-have but don't rely or depend on it like you do with rubber on the road. More things to be mindful about.
This past winter I ran mostly in my Xero DIY sandals and Tabu booties and the Xeros have no traction left under the balls of my feet. I considered maybe trying to put screws or spikes through my Luna Mono sandals for ice but went a different way. I realized running on ice without good traction is a great form exercise. You can't over-stride or push off with too much force on ice without tread so you have to do short, quick, light steps.
It's another reason for unshod: you've got traction barefoot but bare feet are also exposed and vulnerable. You can't go unshod over-striding and pushing off with too much force on paved surfaces or your skin just gets beat up after a couple miles at the longest. You end up running on paved surfaces barefoot the same way most people run on dirt and gravel in shoes: careful where you step and minimizing slip and friction.
